The purposes of this application are: a) to bring the ventilation in the animal rooms in two buildings to 10-16 air changes per hour. b) to add exhaust ducts to increase the capacity for removing air from hoods housing animals treated with volatile agents. c) to replace a cage washer for a 10,000 square foot animal facility. These changes will improve the animal care facilities and environment for animals being used for biomedical research at the University of Nebraska Medical Center. They will also expedite research and insure safety for personnel using hazardous volatile compounds. The replacement of the cage washer will make it possible to continue to operate the facility successfully as a barrier type animal facility.